Designing a Self-Report Fatigue Questionnaire for Intercity Bus Drivers

Intercity Bus Network is the main passenger transportation system in Iran. Since driver fatigue (physical, mental) causes accidents, developing tools to identify fatigue is necessary. Among all the tools available to assess driver fatigue, questionnaire could be the most useful tool, due to the direct involvement of the driver in measuring fatigue. This study was conducted to develop a self-report fatigue questionnaire for intercity bus drivers.
To develop the questionnaire, first 30 bus drivers were interviewed. Interviews continued until the time of data saturation. Initial items were extracted from interview analysis. After face validity confirmation, Lawshe method was used to determine content validity of the questionnaire. Items’ acceptance was performed based on CVI> 0.75 and CVR> 0.99. Cronbach's alpha coefficient, with acceptance criteria≥ 0.75 was also used to determine the reliability of the questionnaire. All analysis was performed by SPSS Version16 software.
Based on all interviews, 28 items were extracted and face validity index was confirmed for all of them. Seven items were eliminated due to low necessity index (CVR 0.99, CVI> 0.75). The reliability of the final questionnaire was also confirmed (α= .93).
The questionnaire designed and validated in this study could be a useful tool to assess the drivers’ fatigue in intercity bus network.